Assessing Parkinson's Rest Tremor from the Wrist with Accelerometry and Gyroscope Signals in Patients with Deep Brain...

Area of Science:

• Biomedical Engineering
• Neuroscience
• Wearable Technology

Background:

• Wearable sensors, particularly inertial measurement units (IMUs), are crucial for assessing motor symptoms in Parkinson's disease (PD).
• Standardization is needed due to the heterogeneity of methods and clinical settings in current wearable sensor research for PD.
• This study focuses on comparing accelerometry and gyroscope signal features for wrist-based tremor assessment in PD.

Purpose of the Study:

• To compare previously proposed accelerometry and gyroscope signal features for tremor assessment at the wrist in Parkinson's disease patients.
• To evaluate the correlation and reliability of these features with clinical tremor severity scales.
• To identify optimal signal features for monitoring tremor in PD patients undergoing deep brain stimulation (DBS).

Main Methods:

• An IMU recorded accelerometry and gyroscope signals from the wrist of 18 PD patients during DBS 'on' and 'off' states.
• Calculated signal features included mean linear acceleration, mean angular velocity, RMS, maximal amplitude, and power in the 3-7 Hz band.
• Features were correlated with the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) item 3.17 using linear regression and ICC for reliability.

Main Results:

• All tested signal features strongly correlated with the MDS-UPDRS tremor amplitude scale.
• Accelerometry features demonstrated a stronger correlation (r = 0.964-0.970) with tremor ratings than gyroscope features (r = 0.942-0.956).
• Mean linear acceleration was the best performing feature (r = 0.970, R² = 0.940) with high reliability (ICC = 0.921).

Conclusions:

• Both accelerometry and gyroscope signal features are effective in characterizing wrist resting tremor in PD patients.
• Simpler accelerometry features, like mean linear acceleration, are recommended for MDS-UPDRS item 3.17 assessment in PD patients with DBS using wrist-worn IMUs.
• Further research is warranted to enhance the validity and utility of wearable technologies for PD management.